A fatal defect of ultrasonic fingerprint identification is that it cannot be pasted. If a film is added to the screen of the mobile phone, it means that the ultrasonic signal needs to penetrate hundreds of meters of additional film to identify fingerprints. Even if the ultrasonic signal can penetrate the fingerprint, it will interfere with the quality of the fingerprint image. In this regard, Samsung officials also said that the S 10 series of ultrasonic screen fingerprints can be affixed with thin traditional films, but they are not compatible with tempered films. Because the thickness of the tempered film is generally 300-400m, after pasting, the ultrasonic signal under the screen may not penetrate. From a well-known UP main test video, it is known that ultrasonic fingerprint identification cannot work because of the thickness problem after the ordinary toughened film is pasted.
V-film is a kind of coating with special formula, which is coated on the surface of PET, P0, PVC and EVA film substrates to achieve the effect of blocking ultraviolet rays and short-wavelength visible light.